I've heard (probably in that Lynn Truss Eats, Shoots & Leaves book) that exclamation point is more common in America. I like saying exclamation mark because then it's more like question mark. But that could just be me being fussy.

I opted for "exclamation mark" over "exclamation point" on the grounds that the symbol in question is more than just a point -- it's a point with a vertical line over it. But that's just me being fussy. Is there some more reasonable reason to choose "exclamation mark"?

I don't usually use more than one exclamation mark, but when I do, I use an odd number of them!!! For example, three exclamation marks, or five!!!!! Or even seven, if I'm feeling particularly maniacal!!!!!!!

For some reason, an even number of exclamation marks just looks wrong!!